Single dose oral ibuprofen and diclofenac for postoperative pain

Ibuprofen and diclofenac are two widely used non-steroidal anti-inflammatory (NSAID) analgesics. It is therefore important to know which drug should be recommended for postoperative pain relief. This review seeks to compare the relative efficacy of the two drugs, and also considers the issues of safety and cost.

To assess the analgesic efficacy of ibuprofen and diclofenac in single oral doses for moderate to severe postoperative pain.

Randomised trials were identified by searching Medline (1966 to December 1996), Embase (1980 to January 1997), the Cochrane Library (Issue 3 1996), Biological Abstracts (January 1985 to December 1996) and the Oxford Pain Relief Database (1950 to 1994). Date of the most recent searches: July 1998.

The inclusion criteria used were: full journal publication, postoperative pain, postoperative oral administration, adult patients, baseline pain of moderate to severe intensity, double-blind design, and random allocation to treatment groups which compared either ibuprofen or diclofenac with placebo.

Data were extracted by two independent reviewers, and trials were quality scored. Summed pain relief or pain intensity difference over four to six hours was extracted, and converted into dichotomous information yielding the number of patients with at least 50% pain relief. This was then used to calculate the relative benefit and the number-needed-to-treat (NNT) for one patient to achieve at least 50% pain relief.

Thirty-four trials compared ibuprofen and placebo (3,591 patients), six compared diclofenac with placebo (840 patients) and there were two direct comparisons of diclofenac 50 mg and ibuprofen 400 mg (130 patients). In postoperative pain the NNTs for ibuprofen 200 mg were 3.3 (95% confidence interval 2.8 to 4.0) compared with placebo, for ibuprofen 400 mg 2.7 (2.5 to 3.0), for ibuprofen 600 mg 2.4 (1.9 to 3.3), for diclofenac 50 mg 2.3 (2.0 to 2.7) and for diclofenac 100 mg 1.8 (1.5 to 2.1). Direct comparisons of diclofenac 50 mg with ibuprofen 400 mg showed no significant difference between the two.

Both drugs work well. Choosing between them is an issue of dose, safety and cost.